Contacting device for a dynamo-electrical igniting machine driven by a mainspring



March 1957 H. SCHAFFLER-GLOSSL CONTACTING DEVICE FOR A DYNAMO-ELECTRICAL IGNITING MACHINE DRIVEN BY A MAINSPRING Filed April 5, 1955 INVENTOR.

United States Patent CONTACTING DEVICE FOR A DYNAMO-ELEC- TRICAL IGNITING MACHINE. DRIVEN BY A MAINSPRING Hans Schafller-Gliissl, Vienna, Austria Application April 5, 1955, Serial No. 499,456 Claims priority, application Austria April 28, 1954 4 Claims. (Cl. 310--69) This invention relates to a contacting device for a dynamo-electrical igniting machine driven by a mainspring and intended particularly for the firing of exploders.

Such a contacting device is disclosed, e. g., in my U. S. Patent No. 2,563,494, and comprises first and second input terminals, first and second output terminals, said first output terminal being electrically coupled to said first input terminal, a first stationary contact electrically connected to either of said second terminals, a second stationary contact electrically connected to said first output terminal, and a first contacting member permanently connected to the other of said second terminals and operable by the mainspring to temporarily engage said first stationary contact.

, It is a general object of the invention to develop that known contacting device to prevent a current flow while the mainspring is being wound up.

If the instructions for operation are observed, which require that the ignition line should be disconnected from the igniting machine during the Winding-up operation, such current flow during the winding-up of the mainspring will be entirely insignificant. On the other hand, if that instruction is disregarded the current produced during the winding-up of the mainspring can assume a value sufiicient for igniting one or another of the detonators which are arranged in the igniting loop; this may have serious consequences.

The invention solves the problem of designing a contacting device of the type described above in such a manner that such an undesired igniting current cannot flow at all. I

i To this end the invention provides a contacting device of the type described above, which comprises a second contacting member permanently electrically connected to said first contacting member and operable to temporarily engage said second stationary contact, and coupling means between said first and second contacting members providing between them for an amount of lost motion sufiicient to cause said second contacting member to engage saidsecond stationary contact only after the first contacting member has engaged said first stationary contact during theunwinding of the mainspring, and to engage said second stationary contact at least as long as the first contacting member engages said first stationary contact during the winding-up of the mainspring.

In a contacting device of the type described, which comprises a stationary contact disk carrying said'first stationary contact and a strip forming said second stationary contact and in which said first contacting memher. is rotatable by the mainspring to temporarily engage said first stationary contact, the second contacting member may comprise electrically connected first and second wiping contacts and may be rotatable to movesaid first, wiping contact into temporary engagement with said sec-.

ond stationarycontact strip and the permanentelectrical connection between said first andsecond contacting mem' bers may be effected by a third wiping contact mechani- 2,784,328 Patented Mar. 5,-1957 cally and electrically connected to said first contacting member and engaging said second wiping contact.

An illustrative embodiment of the invention is represented in the accompanying drawing, which shows a perspective view of the general arrangement of those parts of the igniting machine which are necessary for an understanding of the invention, together wth a circuit diagram.

The igniting machine comprises in the known manner the drive gear 1 in mesh with the drive pinion 2 of the igniting dynamo 11 and connected to a ratchet wheel 3, which cooperates with a locking and release pawl (not shown). The drive wheel 1 is also coupled to a control disk 4. A second control member 5, consisting of a camwheel, is freely rotatable on a sleeve 4a, which is connected to the control disk 4 and surrounds the shaft ia'of the drive gear 1. The camwheel 5 has a concentrio guide slot 5', in which a driving pin 4b of the control disk 4 is slidable. Thus the camwheel 5 can be coupled to the control disk 4 in both directions with a lost motion which corresponds to the length of slot 5. The free end of the control disk sleeve 4a hasfirmly connected thereto the inner end of the mainspring 40, whose second end is afiixed to the stationary spring housing (not shown).

The camwheel S has insulatedly afiixed thereto a contact spring 5", which comprises three parts designated 5a, 5b, and 50, respectively. The several parts of the Contact spring cooperate with contact paths 8, 9, and 10 arranged on a stationary insulating disk 7, which surrounds the control disk sleeve 4a. The spring part 5:: cooperates with a slip ring 8 connected to the output terminal 13. Spring part 512 cooperates with a circuit closing contact path or first stationary contact 9 and the shortest spring part 5c cooperates with a wiping contact path 6a of an insulating disk 6, which is disposed between the camwheel 5 and the insulating disk 7 and is coupled to be driven by the former. That contact path 6a is electrically connected to a wiping contact spring 6b, which cooperates with the short-circuiting contact path or second stationary contact 10 on the insulating disk 7 and represents a winding drag contact, whose mode of operation will be explained hereinafter.

The camwheel 5 constitutes a first rotary disk carrying the first contacting member 5]) and rotatable by the mainspring 40 to move the first contacting member 5b into temporary engagement with the circuit closing contact 9 to close the igniting circuit which leads from brush or first input terminal 11a over winding 15, first output terminal 12, line 14, detonators 16, second output terminal 13, slip ring .3, contact springs 5a, 5b, and circuit illtzsing contact 9 to brush or second input terminal The insulating disk 6 constitutes a second rotary disk carrying the second contacting member which comprises the electrically connected first and second wiping contacts 6b and 6a, respectively; The second rotary disk 6 is rotatable to move the first wiping contact 6b into temporary engagement with the short-circuiting contact strip 10 to short-circuit the igniting circuit identified above since the contact 16 is electrically connected to the first output terminal 12. stitutes a third wiping contact, electrically connected to the and engages the second wiping contact 6:: to effect a permanent electrical connection between member 5b and the second contacting member 6a, 6b.

The leads between the compound-excited direct-current ignition dynamo 11 and the two terminals 12 and 13 for the ignition line 14 firing the detonators 16extend on: collector brush 11a throughthe 12, which is The spring part 5c conwhich is mechanically. andfirst contacting member 5b the first contacting the other hand from the second brush 11b to the circuit closing contact path 9 and from the slip ring 8 to the terminal 13.

The mode of operation of the contacting device during the igniting phase is similar to that according to my prior patent mentioned hereinbefore. After release of the mainspring 4c the camwheel 5 remains still for a time. Only after the control wheel 4, rotating in the clockwise sense, has performed three quarters of a turn is the camwheel driven along by the control wheel 4 through the intermediary of pin 4b. After a rotation through further approximately three quarters of a turn an extension which is formed on the camwheel 5 and carries the tripartite contact spring 5" engages one engaging edge on the insulating disk 6 and drives also the latter in the clockwise sense. The spring part 5b of the tripartite contact spring 5", which is insulatedly arranged on the camwheel 5, engages the circuit closing contact path 9 of the insulating disk 7 and in conjunction with the spring part 5a wiping along the slip ring 8 closes the igniting circuit. After an igniting current has flown for about four thousandths of a second the contact spring 6b connected to contact path 6a reaches the short-circuiting contact path 10 and short-circuits the igniting machine to interrupt the igniting current.

The winding-up of the mainspring 4c begins while the igniting machine is in its short-circuited position and proceeds as follows: While the contact spring 6b connected to the contact path do on the insulating disk 6 remains on the short-circuiting contact path 10 to maintain the igniting machine short-circuited, the control disk 4 is moved in the anticlockwise sense during the winding-up operation. During that movement the pin 41) of disk 4 slides in the concentric guide slot 5" extending in the camwheel 5 around about 2 4 of a circle. Thus the cam- Wheel 5 is driven by the control Wheel 4 only after the latter has performed three quarters of a turn. The extension on the camwheel 5 which carries the tripartite contact spring 5 then clears the engaging edge of the insulating disk 6, which still remains in position with the contact spring 6b in engagement with the contact path 10, so that the igniting machine remains shortcircuited. During the rotary movement of camwheel 5 the spring part 5b of the tripartite contact spring Wipes over the contact path but in doing so cannot cause an igniting current to flow because there is a short circuit between the two terminals 32 and 13. After approximately a full turn of the camwheel 5 its extension carrying the tripartite spring engages the second engaging edge of the insulating disk 6 and drives the same in the anticlockwise sense. Thus the contact spring 6b leaves the sh'orbcircuiting contact path 10 and the igniting circuit could now be closed by the part 5b of the contact spring 5". This is not the case, however, because in the meantime, after about 1% turns 'of the drive gear 1 in the anticlockwise sense, the mainspring 40 has been completely strained.

It is thus apparent that the extension of the first rotary disk 5 which carries the spring 5" and the engaging edges of the second rotary disk 6 constitute coupling means providing between said disks 5, 6 and also between the first and second contacting members 512 and 6a, 612, for lost motion amounting to a major portion of a turn to cause the first wiping contact 6b to engage the shortcircuiting contact strip 10 only after the first contacting member 5b has engaged the circuit closing contact 9 during the unwinding of the mainspring 40, whereas the first wiping contact 61; engages the short-circuiting contact strip 10 at least as long as the first contacting member 5b engages the circuit closing contact 9 during the windingup of the mainspring 4c.

The pin 4!; of the control disk 4 and the camwheel 5 formed with the slot 5' constitute coupling means pro viding between the mainspring 4c and the first contacb ing member 5b for lost motion amounting to a major portion of a turn. Thus the winding-up of the mainspring, requiring more than one and less than two turns, e. g. 1% turns, can be performed without the first contacting member 5b engaging the circuit closing contact 9 during a major initial portion of the first winding-up turn of the mainspring.

Thus the flow of igniting current during the winding-up of the mainspring is eilectively prevented.

What I claim is:

i. In a contacting device for a dynamo-electrical igniting machine driven by a mainspring, comprising first and second input terminals, first and second output terminals, said first output terminal being electrically coupled to said first input terminal, a first stationary contact electrically connected to either of said second terminals, a second stationary contact electrically connected to said first output terminal, and a first contacting member electrically connected to the other of said second terminals and operable by the mainspring to temporarily engage said first stationary contact, the provision of a second contacting member permanently electrically connected to said first contacting member and operable to temporarily engage said second stationary contact, and coupling means between said first and second contacting members providing between them for an amount of lost motion suficient to cause said second contacting memher to engage said second stationary contact only after the first contacting member has engaged said first stationary contact during the unwinding of the mainspring and to engage said second stationary contact at least as long as the first contacting member engages said first stationary contact during the winding-up of the mainspring.

2. In a contacting device for a dynamo-electrical igniting machine driven by a mainspring, comprising first and second input terminals, first and second output terminals, said first output terminal being electrically cou pled to said first input terminal, a stationary contact disk carrying a first stationary contact electrically connected to either of said second terminals and a second stationary contact electrically connected to said first output terminal, and a first contacting member electrically connected to the other of said second terminals and operable by the mainspring to temporarily engage said first stationary contact, the provision of a second contacting member comprising electrically connected first and second wiping contacts and rotatable to move said first wiping contact into temporary engagement with said second stationary contact, a third Wiping contact mechanically and electrically connected to said first contacting member and engaging said second wiping contact, and coupling means etween said first and second contacting members pro viding between them for an amount of lost motion sufficient to cause said first wiping contact to engage said second stationary contact only after the first contactingv member has engaged said first stationary contact during the unwinding of the mainspring and to engage said second sta nary contact a least as l ng as the first con a ting member engages said first stationary contact during the winding-up or the mainspr 37-111 a cont cting d vice r a yn moclec r l igniting ma hine' riven by a ma p p ng first and second input terminals, first and second output terminals, said first output terminal being electrically coupled to said first input terminal, a stationary contact disk member and rotatable to move said first wiping contact into temporary engagement with said second stationary contact, and a third wiping contact mechanically and electrically connected to said first contacting member and engaging said second wiping contact, said second rotary disk being coupled to said first rotary disk with lost motion amounting to a major portion of a turn to cause said first wiping contact to engage said second stationary contact only after the first contacting member has engaged said first stationary contact during the unwinding of the mainspring and to engage said second stationary contact at least as long as the first contacting member engages said first stationary contact during the winding-up of the mainspring.

4. In a contacting device for a dynamo-electrical igniting machine driven by a mainspring adapted to be completely Wound up by being given more than one and less than two turns, comprising first and second input terminals, first and second output terminals, said first output terminal being electrically coupled to said first input terminal, a stationary contact disk carrying a first stationary contact electrically connected to either of said second terminals and a second stationary contact electrically connected to said first output terminal, the combination of a first contacting member electrically connected to the other of said second terminals and rotatable by the mainspring to temporarily engage said first stationary contact,

a second contacting member comprising electrically connected first and second wiping contacts and rotatable to move said first wiping contact into temporary engagement with said second stationary contact, a third wiping contact mechanically and electrically connected to said first contacting member and engaging said second wiping contact, coupling means between said first and second contacting members providing between them for lost motion amounting to a major portion of a turn to cause said first wiping contact to engage said second stationary contact only after the first contacting member has engaged said first stationary contact during the unwinding of the mainspring and to engage said second stationary contact at least as long as the first contacting member engages said first stationary contact during the winding-up of the mainspring, and coupling means between said mainspring and first contacting member providing between them for lost motion amounting to a major portion of a turn to enable the mainspring to be wound up completely without engagement of said first stationary contact by said first contacting member during a major initial portion of the first winding-up turn.

References Cited in the file of this patent UNITED STATES PATENTS 2,563,494 Glossl Aug. 7, 1951 

